Spectators in Moscow were treated to the site of humorously designed makeshift aircraft plunging into the Muskova River during the Red Bull Flugtag Moscow 2011 competition. 38 teams took part at the Flugtag – which means “flying day” – a competition in which teams in fancy dress attempt to pilot human-powered, home-made flying machines off a six-meter-high platform into water.

Photo: A makeshift aircraft plummets into the Moskva River during the Red Bull Flugtag Moscow 2011 competition. (Photo by Sergei Karpukhin/Reuters)

Volunteers use flour to clean birds following an oil spill caused by an incident involving two tankers damaged in a storm in the Kerch Strait, in the village of Vityazevo near the Black Sea resort of Anapa, Russia on December 20, 2024. (Photo by Sergey Pivovarov/Reuters)

A man dressed as a bear and wearing a protective face mask amid the outbreak of the coronavirus disease (COVID-19) stands in front of a fountain in central Kyiv, Ukraine on August 11, 2020. (Photo by Valentyn Ogirenko/Reuters)

People look at a black bear at the Chengdu zoo amid the coronavirus outbreak on March 26, 2020 in Chengdu, Sichuan Province of China. (Photo by Wang Lei/China News Service via Getty Images)

Brown bear cubs eat out of garbage bins at a residential area near the forest in Sarikamis district of Kars, Turkiye on May 30, 2023. (Photo by Huseyin Demirci/Anadolu Agency via Getty Images)

A polar bear fast asleep at London Zoo. (Photo by Fox Photos/Getty Images). 1961

A adorable bear cub cant get enough of playing buckaroo – as it hangs onto its mum splashing about in a river. His mum was attempting to catch a fish supper for the pair as the plucky cub continued to jump on her back. And as she was concentrating on her meal the young bear became a distraction. So she sprung into life with him on her back before he was tossed into the water much to his delight. (Photo by Lisa Sidorsky/Caters News)

The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)